Calculator.



H. A. WRENN.

CALCULATOR.

APPLCATlON FILED JUNEZ, 1915. 1,181,193 Patented May 2,1916.

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H. A. WRENN.

CALCULATOR. APPLICATloN FILED JUNE 26.1915.

Patented May 2, 1916.

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CALCULATOR. APPUCATN FILED UNE 25,1915. 1, 1 81,81 9. Patented May 2,1916 3SHEETS-SHEET 3|- UNTED STATES PATENT oFiiioE.

HERBERT A. "TR'ENN, WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OF ONE-HALF TO STERLING H. WATSON, OF WASHINGTON, DISTRICT OF COLUMBIA. l

CALCULATOR'.

Specification of Letters Patent.

To all whom it may concern Be it known that I, HERBERT A; WRENN,"

acitizen of the United States, residingat VVashingto-n, District ofColumbia, have inf vented certain new and useful Improvements inCalculators, of which the followning. is a specification, referencebeing had therein to the .accompanying drawing.

This invention relates to new and useful improvements in calculatingapparatus, designed especially for adding, subtracting, multiplying anddividing.

The invention comprises-a simple and eilicient apparatus of'thisnaturehaving various details o-f construction, combinations and arrangementsof parts which will be hereinafter fully described, shown in theaccompanying drawings and then specifically defined' in the appendedclaims.

-My invention is illustrated in the accompanying drawings, in which:

Figure 1 is a frontI elevation of a calculating apparatus, parts beingIbroken away to better illustrate featuresl of the invention. Fig. 2 is acentral -ve'rtical sectional view through the calculator. Fig. 3 is anenlarged detail in elevation of the transferring or carrier features ofthe invention. Fig. 4:

- is an enlarged detail p'erspectiveview showing a resilient tensionmeans.. Fig. 5 is a detail perspective view of a portion of an endlesschain with a modified ,link utilized for clearingl the wlieels. Fig. 6is a detail view of a feature of the invention for imparting anintermittentl movement' to the endless.

chain, and Fig. 7 is a. detail view of a portion of the carrier device.

Reference now being had to the details of the drawings by numeral, 1designates the frame of the calculator which may be of any shape or sizeand mounted within the casing Iis a .shaft 2 upon which a series ofnumeral bearing wheels 3 are journaled which carry two sets of numeralsupon the projecting portion 4 thereof, one set .being designated in thedrawings by numeral 5 and the other set by numeral 6,

numerals at the left hand corner of the facehe latter bearing the smallupon which the larger numerals appear.

-Said wheels, details of which are shown in I Fig. 3 of the drawings,are made preferably of a. stamped up piece of metal with an integral cam7 upon one face thereofI and each wheel has a cylindrical bearingportion 7.

Fastenedfto the upper surface of the bottom of the casing is across-piece S. a detail of a portion of which is shown in Fig. 4 of thedrawings. and which has notches 9 upon theJ forward edge thereof.Resilient, bailshaped members 10 have their opposite sides.

passing through the'notches and horizontal portions 11 pass underneaththe crosspiece and the hooks l2 at the ends thereof engage over .therear edge of the cross-piece, said bail-shaped portion being disposednormally at an angle, as shown inthe drawings, and

Patented May 2, 1916.

being resilient andserving as a tension means 'A' for the purposepresently to be described. Endless chains, made up of links 13, areconnected together and everyl tenth link, which is designated by-numeral14," a detail of which is shown in Fig. 5, differentiates from the otherlinks in having theprojecting ends lwhich are provided for the purposeof clearing the wheels. y Said links engageover the projecting portions4 which serve as the equivalents ofteeth of a cog .wheel and which chainalso engages over a 'columns of numerals from 0 to 9,' is adapted to beshifted for the purpose of adapting the apparatus for use in addingdollars and cents or for calculating numbers generally, v

the sheet of numerals being at its extreme limit to the, right whencalculating dollars and cents andin which position the columnl ,ofnumerals at the extreme right would be .obscured by the opaque portion24 upon a transparent covering 25. When the numeral carrying sheet isshifted to theextreme left, the column -ofl figures to the extreme leftof the sheet would be covered up by the opaque strip 27 at the edge ofthe glass cover and the column at the extreme right Awould be disclosed,adapting the apparatus for use in adding, subtracting, multiplying ordividing numbers. The surface upon which said columns of figures appearhas vpreferably different colored sections, the first Idesignated bynumeral 18 being red, the shading,

ios

designated by numeral 19, being green, the

Asection red and the section 21 green,

forming a convenient means for indicating units, tens, hundreds,thousands, etc. lThe means tor imparting intermittent movements to thechains consists V'of a bar tion ofone end of a spring 31, the other end.of the spring being connected to any aperture 32 inthe flanged bar 33',`which latter also has in lone edge thereofv notches Se in which the'bars 28 are guided in their longitudinalmovements. The lower end of'each bar 28 has an angled lprojection' which in Fig.2, and, when adownward thrust .h is imparted to thebar 28,'said projectionl '28, adetail ofl one of lwhichis shown .Fig.' 6, which has an offset 29between its vends and is apertured. at 30 for the recepvprojects betweenthe links,'as shown `clearly cominoV ao'ainsttheflower end of the link`r 23 D .will movethe latter and impart a partial revolution to thecarrier wheel about which thechain passes. The upper end of each bar 28has an aperture 36 which receives a pivotal pin 3T, .secured in anaperture 39' inthe L-shapedbarllO, av detail of which is shown in Figi.Said bar 40 has apertures vand 42 Yregistering with each otherandcarriesa pivotal pin 43 upon which an anti friction roller te is journaled,said wheel being adapted to travel upon the 'surface of the cam 7.' l..

A bail-shaped member 45 is pivotally mounted upon the pins .46 and 4l',asl shown in" solid lines in Fig. l, and has a handle 48projectingthrough `a slot 49m one wall of the c asing, said bail-shapedmember being. positioned'beyond thevarious series ot chains andvadjacent to their lower ends,

same normally out of the 'path of the chains.

.A'second bail-shaped member is designated by numeral 51', the arms 'ofwhich near their ends are pivotally mounted upon the pins"52.` 'A-spring 53, is secured at one endlto the member 51 and its other endsecured to the casing at 54:. A handle 55, which is secured to themember 51, is .shown in solid lines in Fig. 1 and in dottedlines and aspring 50, secured tothe casing, bears'l against the member Zl5 andtends to hold the in Fig. 5, and'hasa movement in a curvedv movement ofsaid member in opposite directions. The transverse portion 5l of themember 51 is adapted to be thrown so as to engage'theseveral'projectingportions 15 of the linkslt when it is desired to clear all of thewheels, it being understood that,v before the wheels may be clearedl` itwill be necessary to actuate the bail-shaped. memu ber 45 so that thechains will be thrown out of the. paths of the projections 35 of the'bars28. In the chainsillustrated, every tenth link is of theconstructionv shown in Fig. .5 and 4provided lwith the projecting `slot56,' the ends of the slots limiting the bail-shaped member 51 to withthe various projecting portions 15 ol 1 menare ends \15 and whatevernumerals may .be

bel caught thereby and the carrier wheelsactuated by the various 'cha-mswill be re-` turned to O.

ln operation of-the apparatus for adding, the fingers ot'the. operatorare placed upon the particular numeral about which the marginal edgeofthe link is positioned. rlhechain is' given downward movement untilthe finger comes in contact with the edge 17. As the links of the chainturn in .disclosed at the sight opening on the vari- 'ous carrierwheels, when the member ll swung downtoward a horizontal position, theprojecting ends l5 of the links le will contact with the uppertraiisverse.portion y' of the resilient bail-shaped member l0, the

latter will spring back to its normal position, shown in Fig. v2,exerting a tension upon the chain which willtend to aline the numeralat-the slot. lVhen the link on a chain, representing the highest numeralin the column, is brought down to the edge 17, vwhich designates a stop,the cam upon the face of the wheel to the right will have raised 'thel.shaped -bar l() toits vhighest upper limit i' and, when an additionalmovement 1s imparted to the same chain' to add another number, the endoit the `cam will pass by the antifriction roller and the' spring 3l',which is put under tension as the bar Ll() is being thrown upward, willquickly return the bar 28 to its normal position andY the projection 35coming in contact with the "link upon an adjacent chainl the linkscausing the-.chains upon which they appear to be moved correspondingvdis-' tances, the bail-shaped -member t5 first having ben tilted `out ofthe paths of the projecting ends of the bar 28. in the event -ornitbeing desired teclear any one numeral hearing wheel independent ol theothers. the operator may swing the bail-shaped member l5 through themedium of the handle 48, causing said member ll5 to come in contact withthe various chains and impart an outer movement thereto, sothat theywill clear the projecting point thus'allowing the chain to beumovedfreely upward.

lt will be noted that. wnen the links of the various chains pass by theresilient bailshaped tension device 10, the latter yields lWhen it isdesired to clear the .iso

and quickly springs back to its normal position, causing the chain tobeheld taut and accurately alining the numerals upon the carrier wheels,

In the manipulatlon of the apparatus for use in subtracting,

the amount of the mmuend by the seriesof A numbers at the `left handcorner -on the pro.-

je'ctinglpart of the ace .4 and which are designated by numeral 6, afterwhich the operator actuates the lchains in the same manner as inaddition and -which will show the result bythe series'of numeralsdesignated bynumeral'. f

In the vuse of the calculator for multiplying, assuming for instancethat it is desired to .multiply Qby 25, the finger of the erator' isplaced upon the numeral 2 in the 5 inthe tens column, twice and which'is and then, by placing ing down in the second column to the downto'the stop line 17 the finger upon the link about the numeral 5, in theunits column, draws the lchaindown to the stop and this is repeated livetimes, the equivalent of adding v ivetimes.. Then," the linger of theopten's column, right, and drawn erator 'is placed in the' -numeral 2 inthe third column, representing hundreds, pullthe chain tol the stop linetwice, -and thence the link, designated by numeral equivalent 'of adding25 twenty times. The

. result will appearjat' thesight aperture, designated through 35,.

Pdivisiom the chains are manipulated in order the various numerals 5. Inthe'manipulation of `the vcalculator for to bring the various numerals 6lto designate the dividend the sight aperture, after whichthejchains.are manipulated as in subtraction, the dividend being treated as a n 1rninuendandv the divisor as a subtrahend, 7 lthat is, if. in vthe 'tenscolumn, the link desigejnating the-first numeral in the subtrahend ispulled down tothe stopline 17 and-then the 50. .to be indicated at'thesight slot above. This ldown to the stop line.

v.units numeral of .the sub'trahendA is brought Thev quotientisindicated by pulling down'the chain at the exmovement extremicl fteach time a quotient numeral is thc various wheels are actuated by thechains in order to disclose In the manipulation 'of the apparatus forthe various uses for whic the tension means to aline-'the-numerals is itis provided,

the' same,'that is the yielding bail-shaped A member 10 quickly applyingthe tension to 'the chains to cause the numerals upon the carrier wheelsto aline, and at the comple positioned, to return the wheels to desigivWhat I claim to be new is 1. In a calculating machine, a series otcarrier wheels mountedc therein, vtension members, chains madeup oflinks moving 'about `said carrier wheels and said tension the latteradapted to aline the l members, links ofi the chains,

2. In a calculating machine, a series of carrier wheels mounted therein,chains made up of links moving about said carrier wheels,

stationary,

the tilting of the bail-shaped member 45,

bail-shaped tension members' about which the links of said chains pass,A

i treme leftl end of the series, an intermittent being-impartedtothechain at the manipulation is repeated until the number f i remainingdivisor, the remainder being indicated at the in the dividend is lessthan the sightaperture at the right of the sight slot.

ing the the latter ladapted to aline the said links. the- 3, In alcalculating machine, a `series of carrierwheels mounted therein,Vtension members, chains made upfof links movable about'the carrierwheels and saidtens'ion members,l the'latter adapted to aline the vlinksof the chains, longitudinally movable,

spring-pressed bars adapted to engage the links of the chains, and meansoroperating saidbars in one direction.

4'. In a calculating machine, a series of carrier wheels mountedtherein, chains made up of links movable about the carrier wheels,longitudinally movable, springvpressed 'bars normally in engagement`with said links for causing an intermittent movement to be imparted tothe chains,l and means for throwlinks out of the paths' of the engagingend of said bars to allow the, chains to be operated in. reversedirection.

In'testimony whereof I hereunto atlin mysignature in presence ofltwowitnesses.

Witnesses:

. A. L. HoU'GH, l LS. WATsoN.

HERBERT A. VRENN. v

